Reducing visible aerosol generation during phacoemulsification in the era of Covid-19

Abstract

Objective To assess potential methods of reducing visible aerosol generation during clear corneal phacoemulsification surgery in the era of Covid-19. Methods Aerosol generation during phacoemulsification was assessed using a model comprising a human cadaveric corneoscleral rim mounted on an artificial anterior chamber. Typical phacoemulsification settings were used and visible aerosol production was recorded using high-speed 4K camera. Aerosolisation was evaluated under various experimental settings: Two different phacoemulsification tip sizes (2.2, 2.75 mm), varying levels of corneal moisture, the use of suction and blowing air in the surgical field, the use of hydroxypropyl methylcellulose (HPMC) coating of the cornea with a static and moving tip. Results This model demonstrates visible aerosol generation during phacoemulsification with a 2.75-mm phacoemulsification tip. No visible aerosol was noted with a 2.2-mm tip. The presence of visible aerosol was unrelated to corneal wetting. Suction in close proximity to the aerosol plume did not impact on its dispersion. Blowing air redirected the aerosol plume toward the ocular surface. Visible aerosol production was abolished when HPMC was used to coat the cornea. This effect lasted for an average of 67 ± 8 s in the static model. Visible aerosol generation was discerned during movement of the 2.2mm tip toward the corneal wound. Conclusions We demonstrate visible aerosol production in the setting of a model of clear corneal phacoemulsification. Visible aerosol can be reduced using a 2.2-mm phacoemulsification tip and reapplying HPMC every minute during phacoemulsification.

Novel Insights into the Transmission of SARS-CoV-2 Through the Ocular Surface and its Detection in Tears and Conjunctival Secretions: A Review

“…As such, endoscopic dacryocystorhinostomy should be classified as a high-risk procedure [ 36 , 37 ]. Aerosol generation has been evaluated during phacoemulsification and suggestions have been made to minimize visible aerosol production by using a 2.2-mm phacoemulsification tip and reapplying hydroxypropyl methylcellulose (HPMC) coating of the cornea every minute during phacoemulsification [ 38 ]. Another study revealed that phacoemulsification did not generate aerosols of 10 μm or smaller with continuous power using 80% longitudinal, 100% torsional, or 80% longitudinal setting with HPMC on the surface [ 39 ].…”

Hypercytokinemia in COVID-19: Tear cytokine profile in hospitalized COVID-19 patients

“…Several ophthalmological societies have issued guidelines with recommended protocols, all agreeing that it is safest to assume that any patient is potentially infected, especially in high risk areas. Aerosol generation has been evaluated during phacoemulsification and should also be considered (Darcy et al, 2020).…”

Creating aerosolized droplets in phacoemulsification

“…Hydroxypropyl methylcellulose coating the cornea decreased droplet production. 2 With phacoemulsification settings at maximum power and no hydroxypropyl methylcellulose on the cornea, the furthest documented droplet radius was 13.2 cm with a 2.75 mm keratome incision ( Fig. B) versus 1.9 cm with a 2.2 mm keratome incision ( Fig.…”